Brain blood flow mystery: does metabolic syndrome hit women harder?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria (Healthy Controls): * 18-45 years old * Normal fasting values for blood glucose (less than 100 g/dl) * Normal values for lipids (LDL cholesterol less than 130 mg/dl, triglycerides less than 150 mg/dl) and HDL (men greater than 40, women greater than 50 mg/dl) * Women must have a predictable menstrual cycle. Females will be studied on cycle days 1-7 to minimize sex hormone differences and their potential confounding effects on vascular outcomes. Oral contraceptives are allowed, and women will be studied during their placebo phase. Inclusion Criteria (Participants with Metabolic Syndrome): * 18-45 years old * Meet at least 3 of the 5 ATP MetSyn criteria. These are: 1. Waist circumference greater than 102 cm (males) or 82 cm (females) 2. Triglycerides greater than 150 mg/dL 3. HDL cholesterol less than 40 mg/dL (males) or 50 mg/dL (females) 4. Blood pressure greater than or equal to 130/85 mmHg 5. Fasting plasma glucose greater than 110 mg/dL Exclusion Criteria (Healthy Controls): * Body Mass Index (BMI) greater than or equal to 25 kg/m2 * Blood pressure over 130/80 mmHg * Meeting any of the 5 MetSyn criteria listed above. Exclusion Criteria (all participants): * Current smoker, defined as more than 5 cigarettes over past 30 days * Current diagnosis or history of: * peripheral vascular disease * hepatic disease * renal disease * lung disease * gastrointestinal disorders/bleeding * hematologic disease * stroke * myocardial infarction * coronary heart disease * congestive heart failure * heart surgery * sleep apnea * autoimmune diseases * HIV * traumatic brain injury, concussion, stroke, or seizures * Asthma * Polycystic ovarian syndrome * Type II diabetes * Currently pregnant or breastfeeding * Current musculoskeletal injury * Medication use known to influence cardiovascular function, other than contraceptive hormones. Broadly, the classes of drugs relate to treating blood pressure, diabetes, cholesterol. * Claustrophobia * Lactose intolerance * Magnesium-restricted diet